Email Warming Glossary - Everything you need to know about email warming

June 20, 2023
Email Warming Glossary - Everything you need to know about email warming

In today's fast-paced digital world, email marketing remains a vital channel for businesses to connect with their target audience and achieve their marketing objectives. However, with evolving algorithms and increasing competition, ensuring the deliverability and effectiveness of your email campaigns has become more challenging than ever. 

This is where the concept of email warming comes into play. Email warming is a strategic approach that involves gradually ramping up your email sending volume and engagement to establish trust with email service providers (ESPs) and optimize your deliverability rates. 

This comprehensive glossary will demystify email warming and provide you with all the essential information you need to leverage this technique effectively. By understanding the ins and outs of email warming, you'll be equipped with the knowledge to improve your sender reputation, increase engagement rates, and achieve better results from your email marketing efforts.

What is email warming?

Email warming is a process that involves gradually establishing a positive sender reputation and improving deliverability rates for your email marketing campaigns. It is akin to building trust with email service providers (ESPs) by demonstrating responsible and sending practices. Instead of bombarding your entire subscriber list with a sudden influx of emails, email warming takes a more gradual approach. It starts with sending a smaller volume of emails to a subset of engaged recipients, and over time, increases the sending volume while closely monitoring performance metrics. This methodical approach allows ESPs to recognize you as a reputable sender, minimizing the risk of your emails ending up in spam folders and maximizing the chances of reaching your audience's primary inboxes. By taking the time to warm up your email infrastructure, you pave the way for enhanced deliverability, improved engagement rates, and ultimately, greater success in your email marketing endeavors.

Email Warming Glossary

Email Warming Strategies

Volume Ramp-up

Volume ramp-up refers to the gradual increase in the volume of email sends over a specific period of time. It is a strategic approach used in email warming to establish a positive sending reputation with internet service providers (ISPs) and maintain good deliverability rates. By progressively scaling up the email volume, marketers can build trust and credibility, ensuring their messages reach the intended recipients' inboxes while avoiding potential deliverability issues. This controlled and phased increase allows for better inbox placement and engagement, ultimately enhancing the overall effectiveness of email campaigns.

Warm-up Schedule

Warm-up schedule is a planned timeline that outlines the gradual increase in email sending volume and frequency during the email warming process. It helps ensure a smooth transition from initial low-volume sends to higher volumes while establishing a positive sending reputation. The schedule typically includes specific intervals and benchmarks, allowing marketers to monitor and adjust their email warming strategy accordingly.

IP Warming

IP warming is the process of gradually establishing a positive reputation for a new or inactive IP address used for sending emails. It involves progressively increasing the volume and frequency of emails sent from the IP address to build trust with ISPs. By following an IP warming strategy, marketers can minimize the risk of their emails being flagged as spam and improve deliverability rates.

Domain Warming

Domain warming is the process of gradually establishing a positive reputation for a domain used in email marketing. It involves implementing a strategic approach to gradually increase the volume and frequency of emails sent from the domain. By warming up the domain, marketers can build trust with ISPs, enhance deliverability rates, and improve the overall success of their email campaigns.

Reputation Warming

Reputation warming refers to the process of gradually building a positive sender reputation with ISPs and email service providers (ESPs). It involves implementing best practices, such as sending high-quality, relevant emails and maintaining a good engagement with recipients. By establishing a positive reputation, marketers can enhance email deliverability and ensure that their messages reach the intended recipients' inboxes.

Engagement Warming

Engagement warming is a strategy used to improve email engagement rates by gradually increasing the level of recipient interaction with email campaigns. It involves analyzing and optimizing various engagement metrics, such as open rates, click-through rates, and conversions. By gradually enhancing engagement, marketers can build stronger connections with their audience, improve overall email performance, and increase the likelihood of desired actions by recipients.

List Segmentation

List segmentation refers to the practice of dividing an email subscriber list into smaller, more targeted segments based on specific criteria such as demographics, behavior, or preferences. By segmenting the list, marketers can create more personalized and relevant email campaigns that resonate with different groups of subscribers. This approach allows for more effective targeting, increased engagement, and higher conversion rates.

Engagement-based Segmentation

Engagement-based segmentation is a method of dividing an email subscriber list into segments based on the level of recipient engagement. It involves analyzing engagement metrics such as opens, clicks, and conversions to identify highly engaged subscribers versus those who are less active. By segmenting based on engagement, marketers can tailor their email content, frequency, and offers to suit the preferences and behaviors of different subscriber groups, ultimately improving campaign performance and driving better results.

Warm-up Segment

Warm-up segment refers to a subset of email subscribers that is targeted specifically during the initial stages of an email warming campaign. This segment typically receives lower volumes of emails during the warm-up period to gradually establish a positive sending reputation and ensure good deliverability. By focusing on a warm-up segment, marketers can closely monitor engagement and make necessary adjustments before gradually expanding email sends to the wider subscriber base.

Warming Campaign

Warming campaign is a strategically designed series of email sends aimed at gradually increasing email volumes and establishing a positive sender reputation. This campaign typically follows a warm-up schedule and involves monitoring engagement metrics, deliverability rates, and ISP feedback closely. The purpose of a warming campaign is to build trust with ISPs, maintain good inbox placement, and improve overall email deliverability. It sets the foundation for successful email marketing efforts moving forward.

IP Warm-up

IP warm-up is the process of gradually introducing a new or unused IP address to the email ecosystem to establish a positive reputation with ISPs. During the warm-up period, email senders gradually increase their sending volume and frequency, allowing ISPs to recognize the IP as a legitimate sender. This gradual approach helps to build trust, improve deliverability rates, and mitigate the risk of emails being marked as spam.

Reputation Building

Reputation building refers to the ongoing effort of maintaining and improving the sender reputation associated with an IP address or domain. It involves following best practices, such as sending relevant and engaging emails, maintaining low complaint and bounce rates, and adhering to email industry guidelines. A strong sender reputation is crucial for achieving high deliverability and ensuring that emails reach the recipients' inboxes instead of being filtered as spam.

Engagement Filters

Engagement filters are mechanisms implemented by ISPs to evaluate the level of recipient engagement with incoming emails. ISPs use various engagement metrics, such as open rates, click-through rates, and subscriber interactions, to determine the relevancy and quality of emails. Engagement filters help ISPs prioritize inbox placement for emails that demonstrate higher engagement, while potentially diverting less engaging emails to spam or promotional folders. Marketers need to focus on optimizing engagement factors to enhance email deliverability.

Warm-up Duration

Warm-up duration refers to the length of time required to complete the process of gradually increasing email sending volume and establishing a positive reputation with ISPs. The duration can vary depending on factors like the IP or domain's previous sending history, the quality of email content and engagement, and the specific warm-up strategy employed. A typical warm-up duration ranges from a few days to several weeks, allowing for a smooth transition and optimal deliverability. It is essential to carefully monitor engagement and deliverability during this period.

Monitoring and Optimization

Engagement Metrics

Engagement metrics in email marketing refer to the data and statistics that measure the level of interaction and response from email recipients. These metrics typically include open rates, click-through rates (CTR), conversion rates, and other relevant indicators of recipient engagement. By analyzing engagement metrics, marketers gain insights into the effectiveness of their email campaigns, allowing them to optimize content, subject lines, and overall strategies to improve engagement and drive desired actions.

Deliverability Monitoring

Deliverability monitoring involves actively tracking and analyzing the success of email delivery to the recipient’s inboxes. It includes monitoring metrics such as bounce rates, spam complaints, and inbox placement rates. By closely monitoring deliverability, marketers can identify and address potential issues that may impact the successful delivery of their emails. This proactive approach helps maintain a good sender reputation, optimize email deliverability, and ensure that messages reach the intended audience.

Reputation Monitoring

Reputation monitoring refers to the ongoing observation and evaluation of an email sender's reputation in the eyes of ISPs and email service providers. It involves tracking metrics like spam complaints, bounce rates, and feedback loop data to assess the sender's overall reputation. By monitoring their reputation, marketers can identify any negative trends or issues that may impact deliverability and take corrective measures to maintain a positive reputation, leading to better email deliverability and inbox placement.

Engagement Optimization

Engagement optimization involves strategies and tactics aimed at improving the level of recipient engagement with email campaigns. This includes techniques such as personalized content, compelling subject lines, targeted segmentation, and optimized email design. By continuously testing and refining these elements, marketers can enhance engagement metrics like open rates, CTR, and conversions, resulting in more successful and effective email marketing campaigns. Engagement optimization is key to driving higher levels of customer interaction and achieving campaign objectives.

Inbox Monitoring

Inbox monitoring is the practice of closely observing and tracking the delivery and placement of email messages into recipients' inboxes. It involves using specialized tools or services to monitor the inbox placement rates and ensure that emails are reaching the intended recipients' primary inbox folders rather than being filtered as spam or ending up in promotional or junk folders. By monitoring inbox placement, marketers can assess the effectiveness of their email deliverability strategies and make necessary adjustments to improve overall inbox placement rates.

Inbox Placement Monitoring

Inbox placement monitoring specifically focuses on tracking and analyzing the percentage of emails that successfully land in recipients' inboxes. It involves monitoring deliverability metrics, such as inbox placement rates, spam folder placement rates, and promotional folder placement rates. By closely monitoring these metrics, marketers can identify any issues affecting inbox placement and take corrective actions to improve the likelihood of their emails being delivered to the primary inbox, maximizing visibility and engagement with recipients.

IP Monitoring

IP monitoring involves the continuous tracking and analysis of the reputation and performance of IP addresses used for sending emails. It includes monitoring factors such as IP blacklisting, spam complaints, and sender reputation associated with the IP address. By monitoring IP performance, marketers can identify any issues that may negatively impact email deliverability and take necessary measures to maintain a positive sender reputation, optimize deliverability rates, and ensure successful email campaigns.

Domain Monitoring

Domain monitoring is the process of actively monitoring and managing the reputation and performance of the domain used for email sending. It involves tracking domain-related metrics such as domain reputation, domain blacklisting, and domain authentication status (e.g., SPF, DKIM, DMARC). By monitoring domain performance, marketers can identify any domain-related issues that may affect email deliverability and take appropriate actions to maintain a strong domain reputation and optimize email deliverability rates.

Warm-up Monitoring

Warm-up monitoring involves closely monitoring the progress and effectiveness of an email warming process. It includes tracking engagement metrics, deliverability rates, and sender reputation during the warm-up period. By monitoring these key indicators, marketers can ensure that the warm-up process is proceeding smoothly, identify any potential issues or bottlenecks, and make necessary adjustments to achieve optimal deliverability and reputation building as they gradually increase email volumes. Warm-up monitoring helps maintain control and ensures a successful transition to regular email sending practices.

Email Enhancement and Best Practices

Click-Through Rate

Click-Through Rate (CTR) is a metric that measures the percentage of recipients who click on a link within an email, typically to visit a specific webpage or take a desired action. It is calculated by dividing the total number of clicks by the total number of delivered emails and multiplying it by 100. CTR is an important engagement metric that helps assess the effectiveness of email campaigns and the level of interest generated among recipients. A higher CTR indicates stronger engagement and a greater likelihood of conversions or desired outcomes.

Spam Traps

Spam traps are email addresses or accounts that are intentionally created or used by ISPs, anti-spam organizations, or email blacklist providers to identify senders who engage in spamming practices. These email addresses are not actively used by real individuals and are designed to attract unsolicited emails. If a sender unknowingly sends emails to spam traps, it can negatively impact the sender’s reputation and deliverability. It is crucial for marketers to maintain a clean and healthy email list, adhere to permission-based email practices, and regularly monitor and remove inactive or potential spam trap addresses.

Email Throttling

Email throttling is the deliberate practice of limiting the number of emails sent to recipients within a specific time frame. It is typically employed to manage and control the sending volume to maintain good deliverability and avoid overwhelming ISPs or recipient mail servers. By implementing email throttling, marketers can avoid triggering spam filters, prevent server congestion, and maintain a positive sending reputation. Throttling allows for a controlled and gradual sending approach, particularly during IP warm-up or when sending to a large subscriber base.

Feedback Loop Integration

Feedback loop integration involves the process of connecting an email sender with the feedback loops provided by ISPs. Feedback loops allow senders to receive notifications when recipients mark their emails as spam or unsubscribe from their mailing list. By integrating feedback loops into their email system, marketers gain valuable insights into recipient preferences and engagement, enabling them to address complaints, improve content and targeting, and maintain a healthy sender reputation. Feedback loop integration helps foster better communication and engagement with subscribers while minimizing the risk of being marked as spam.

Subscriber Validation

Subscriber validation is the process of verifying the accuracy and validity of email addresses on a mailing list. It involves checking email addresses for typos, syntax errors, and potential spam traps or inactive accounts. By validating subscribers, marketers can ensure that their email campaigns reach real and engaged recipients, minimizing bounce rates, improving deliverability, and maximizing the effectiveness of their email marketing efforts.

Campaign Optimization

Campaign optimization refers to the continuous improvement and refinement of email marketing campaigns to maximize their performance and achieve desired objectives. It involves analyzing various campaign elements such as subject lines, email content, design, call-to-action, and targeting strategies. Through data analysis, A/B testing, and performance tracking, marketers can identify areas for improvement and make data-driven adjustments to enhance open rates, click-through rates, conversions, and overall campaign effectiveness.

Seed List Warming

Seed list warming is a technique where a subset of trusted and monitored email addresses, known as seed addresses, is used to send test emails during the warm-up phase. Seed addresses belong to real individuals and are used to evaluate inbox placement, email rendering, and engagement metrics within specific email clients or ISPs. By including seed addresses in the warm-up process, marketers can gain insights into how their emails are delivered and displayed, helping them fine-tune their strategies for optimal performance before sending them to the wider subscriber base.

Content Optimization

Content optimization involves tailoring the content of email messages to maximize their impact and engagement with recipients. It includes optimizing subject lines, preheaders, body text, images, and calls to action to deliver relevant and compelling content that resonates with the target audience. By optimizing content, marketers can improve open rates, click-through rates, and overall subscriber engagement, resulting in higher conversions and better campaign outcomes. Content optimization also takes into account factors such as mobile responsiveness, personalization, and segmentation to deliver a personalized and engaging email experience.

Email Personalization

Email personalization is the practice of tailoring email content and messaging to individual recipients based on their preferences, behavior, demographics, or other relevant data. It involves using dynamic content, merge tags, and segmentation techniques to deliver personalized experiences that resonate with each recipient. By personalizing emails, marketers can enhance engagement, build stronger relationships, and improve the effectiveness of their email campaigns by delivering relevant and targeted content that addresses the specific needs and interests of each subscriber.

Deliverability Consulting

Deliverability consulting refers to the services provided by experts or specialized agencies who offer guidance and assistance in improving email deliverability rates. Deliverability consultants analyze factors such as sender reputation, email authentication, list hygiene, and content optimization to identify potential issues and recommend strategies for improving inbox placement and deliverability. They provide valuable insights, best practices, and technical expertise to help marketers overcome deliverability challenges and ensure that their emails reach the intended recipients' inboxes.

Reputation Repair

Reputation repair involves the process of addressing and rectifying a damaged sender reputation. When an email sender's reputation suffers due to factors such as high bounce rates, spam complaints, or being blacklisted, reputation repair techniques are implemented to restore a positive sender reputation. This may include identifying and resolving underlying issues, implementing best practices, improving email authentication, and gradually rebuilding trust with ISPs and email service providers. Reputation repair is crucial for restoring deliverability and ensuring the success of future email campaigns.

Engagement Thresholds

Engagement thresholds are predefined metrics or criteria used to determine the level of engagement required for an email recipient to remain active and continue receiving emails. These thresholds can be based on factors such as open rates, click-through rates, or overall interaction with email content. If a recipient's engagement falls below the established thresholds, it may trigger actions such as re-engagement campaigns, list segmentation, or even removing inactive subscribers from the mailing list. Setting and monitoring engagement thresholds helps maintain a healthy and engaged subscriber base, leading to better deliverability and campaign performance.

Email Compliance

Email compliance refers to adhering to the laws, regulations, and guidelines governing email marketing practices. This includes compliance with anti-spam laws such as CAN-SPAM (in the United States) and GDPR (in the European Union), as well as following industry best practices and email service provider policies. Email compliance involves obtaining proper consent, providing clear opt-out mechanisms, including accurate sender information, and honoring recipient preferences. Adhering to email compliance standards is essential to maintain trust, protect recipient privacy, and ensure legal and ethical email marketing practices.

Understanding email warming and its related terminology is vital for email marketers and businesses aiming to optimize their email deliverability, engagement, and overall campaign performance. The email warming glossary provided a comprehensive overview of key terms and concepts associated with email warming, including volume ramp-up, engagement metrics, warm-up schedule, reputation monitoring, list segmentation, and many more.

By familiarizing themselves with these terms, marketers can effectively navigate the complexities of email warming and implement strategies to build a strong sender reputation, improve inbox placement, and foster higher recipient engagement. From IP and domain warming to subscriber validation and engagement optimization, each term plays a crucial role in the email warming process.

Successful email warming requires a strategic approach, diligent monitoring, and continuous optimization. It is not a one-time event but an ongoing practice that ensures long-term deliverability and engagement success. By incorporating the knowledge gained from this glossary, marketers can implement best practices, make informed decisions, and fine-tune their email warming strategies to achieve optimal results.

As the email marketing landscape evolves and ISPs continue to refine their algorithms, staying up-to-date with the latest trends and practices in email warming is essential. By continuously educating themselves and leveraging the power of email warming techniques, marketers can overcome deliverability challenges, connect with their audience, and achieve higher conversions and business growth.

So, embrace the power of email warming, utilize the insights provided in this glossary, and take your email marketing efforts to new heights. Start implementing effective warm-up schedules, engaging content, and robust monitoring techniques to build a strong sender reputation, enhance deliverability, and maximize the impact of your email campaigns. Remember, email warming is not just about warming up IPs and domains. It's about warming up to your audience and building lasting connections through targeted and engaging communication.

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